//
// Created by wze-zero on 2024/7/9 009.
//
#include <iostream>

using namespace std;

int main() {
    int num;
    cin >> num;
    for (int i = 2; i < num; ++i) {
        if (num % i == 0) {
            cout << "不是质数" << endl;
            return 0;
        }
    }
    cout << "是质数" << endl;
    return 0;
}
